The present invention relates to a strip for making available security elements for electronically securing objects. The strip consists of a carrier web with adhesive labels removably glued thereon, or of tags which are connected with each other for fastening on objects to be priced or secured, wherein only a defined number of labels or tags is equipped with electromagnetically active, or respectively activatable, security elements.
A strip of security labels and a device for producing such a strip are known from European patent, EP 0 682 333 A1. To keep production costs low, only a defined number of labels, or respectively tags, of the strip of security labels is equipped with activatable or electromagnetically active security elements, while the remaining labels, or respectively tags, do not contain security elements, or contain dummy security elements. It has been shown to be advantageous to provide a coating impervious to light, which makes it impossible to determine whether or not the label, or respectively the tag, has a security element, without destroying the label or the tag. Labels with hidden security elements are already known from European patent, EP 0 635 811 A1.
The object of the present invention is to provide a cost-efficient strip, which has an essentially equal detection rate in various monitoring systems.
This object is attained in that the security elements are constituted of at least two types of security elements, which can be detected in different monitoring systems.
In accordance with an advantageous further development of the strip of the present invention it is provided that the security elements are strip elements of low magnetic retentivity, which can be detected in harmonic monitoring systems, and strip elements with a high Barkhausen effect, which can be detected in Barkhausen monitoring systems.
An alternative embodiment proposes, that the security elements are acousto-magnetic security elements or resonant circuit security elements. It is of course also possible to integrate the most diverse types of security elements into a strip in accordance with the present invention and in this way to make it universally usable for the most diverse types of monitoring systems. Nevertheless, it is a preferred embodiment of the strip in accordance with the present invention, wherein two types of security elements are contained in the strip to essentially equal proportions.
An advantageous embodiment of the strip in accordance with the present invention proposes to integrate the security elements into the labels, or respectively tags, in such a way, that it is not possible from the outside to determine whether or what types of security elements are used in the labels.
The theft-protective label consists in particular of a carrier foil for an electromagnetic security element and of a pricing element which is glued on the security element. On its side facing the security element, the pricing element is provided with a layer which has such a low transparency for light waves in the visible range that the securing element cannot be detected from the outside.
In accordance with an advantageous further embodiment of the strip of the present invention it is provided that, for securing the source, the labels or tags can be integrated into the objects to be secured. In this case steps which make the security element invisible to the exterior, can usually be omitted.
In many cases it is desirable for the security element to be deactivated as soon as the customer has correctly paid for the respective secured goods. Therefore an embodiment of the strips in accordance with the present invention provides for the securing elements to be deactivatable. In the case of security elements of low magnetic retentivity or security elements with a great Barkhausen effect, sections of a semi-magnetic or highly magnetic material are arranged for deactivation purposes on the label or tags in such a way, that they prevent a reaction of the low-retentive magnetic material or the Barkhausen material to an exterior alternating magnetic field as soon as they have been pushed to saturation by means of a suitable high deactivation signal.
In the case of resonant circuits, deactivation can be achieved, for example, in that a permanent short circuit penetrating the dielectric layer is generated between two opposite strip conductors.
Alternatively to the solution that some of the labels or tags do not contain any security elements at all it is provided that the labels or tags not provided with security elements are equipped with dummy security elements. This embodiment is already known from the previously mentioned European patent, EP 0 682 333 A1.